Nov. 22 falls on the Friday before Thanksgiving this year, just as it did 50 years ago. And that extraordinary day in 1963 began on the Hill in ways that would seem familiar to the congressional denizens of today.

The House was done for the week, having pushed through spending bills for public works, arms control and military construction in plenty of time to allow a cluster of Texas Democrats to get home for a high-profile political photo op.

The Senate convened for general speech-making and preliminary debate on the bills set for consideration after the weekend: restricting wheat sales to Soviet bloc nations and delivering federal funds for local library construction. As was the custom, then as now, the chore of acting as presiding officer had been parceled out to several of the freshmen with the lunchtime slot assigned to the youngest in the class, 31-year-old Edward M. Kennedy of Massachusetts.

He was in the chair when his brother was killed.

And from that instant, the scene at the Capitol unfolded in ways that may be difficult to comprehend in today’s congressional culture of commuting lawmakers, hyper-partisanship, legislative stasis, saturation live coverage and social-media press relations.

Almost 20 minutes elapsed between when the shots were fired at John F. Kennedy’s motorcade in Dallas and when a messenger delivered the first ominous alert to the president’s youngest sibling, who hustled off the rostrum and called the White House to learn more.

“Will the senator from Vermont yield for an emergency?” Democrat Wayne Morse of Oregon asked, interrupting a speech by Republican Winston Prouty to propose a quorum call while the horrific explanation for the young Kennedy’s departure swept through the chamber.

Sketchy and confused reports — some maintaining the president was merely wounded, others asserting he was dead — had by then started to surge across the otherwise quiet complex. A Capitol Police officer clamored through the halls to alert whichever members he could find. Longworth cafeteria servers stunned their patrons with the news. Staffers clustered in the offices equipped with radios or televisions, or joined groups of members heading to nearby churches.

Majority Leader Mike Mansfield took the Senate floor for just long enough to secure approval of a couple of unanimous consent agreements, then asked colleagues to “stand in recess, pending developments.” The Montana Democrat returned 15 minutes later and summoned all senators to the chamber. Sixty-nine streamed in, an astonishing number by today’s standards for a Friday afternoon when no roll calls had been scheduled.

They all stood and bowed their heads while the chaplain, Methodist minister Frederick Brown Harris, beseeched God to spare a president felled “like a giant cedar, green with boughs” that “leaves a lonesome place against the sky.”

By the time the prayer ended, it had been 20 minutes since JFK had been administered the last rites and pronounced dead at Parkland Hospital.

The senators did not know that. In an era when news services still used a form of telegraphy to send their dispatches, television news was in its infancy and multitasking smartphones were science fiction, the official word did not come for another agonizing third of an hour — because it took The Associated Press and United Press International eight minutes to get their “flash” headlines out after a White House press aide announced that the president was dead.

The most prominent lawmaker waiting by the teletype was Speaker John William McCormack. Though the House was gone for the weekend, the speaker had stayed in town and was having lunch in the Members’ Dining Room when a reporter approached with grim word about his former Democratic colleague in the Massachusetts delegation. McCormack rushed upstairs to the House Press Gallery and hunched his tall, thin, 71-year-old frame over its wire service machines.

When the tickers definitively declared that JFK had died, McCormack became “ashen-faced” and slipped out of the room without saying a word, Roll Call reported at the time. Although he had just moved up to first in the line of presidential succession, he was accompanied by neither staff nor security.

For the congressional community, the bewilderment, anger and grief that took hold of the nation in the ensuing days was even more intense than elsewhere, because Capitol Hill took particular pride in having one of its own in the White House. In 1960, the 43-year-old Kennedy became not only the youngest person ever elected president, but also the first incumbent member of Congress sent to the White House in 40 years.

“We saw him come to this body at age 35, we saw him grow, we saw him rise, we saw him elevated,” went one of the most effusive eulogies delivered in the Senate — and it came from a Republican, Minority Leader Everett McKinley Dirksen of Illinois.

“If at any moment he may have seemed overeager, it was but the reflection of a zealous crusader and missioner who knew where he was going,” Dirksen said just before the funeral the following Monday, at St. Matthew’s Cathedral near Dupont Circle.

Such Victorian rhetoric — preserved in an issue of the Congressional Record with highly unusual black-bordered cover pages — is out of fashion now. And in today’s political climate, it’s tough to imagine an elder statesman of one party paying such complement, even in death, to an opposing party leader’s straining youthful ambition.

Dirksen’s words are not the only reminder about how different Washington’s metabolism was back then. In the days after JFK’s burial, first the Republican and then the Democratic national committees announced that the total suspensions of their partisan activities would extend to the end of the year.

The top GOP presidential aspirants for 1964, Gov. Nelson Rockefeller of New York and Sen. Barry Goldwater of Arizona, the eventual nominee, also stopped campaigning for a full month, leaving just 10 weeks to stump before New Hampshire’s opening primary.

But the 88th Congress got right back to work. It did not use the period of mourning and the impending holiday as excuses to take the whole week off.

A bipartisan Senate majority had given Kennedy the final legislative victory of his life a day before the assassination, clearing a bill raising the debt ceiling to all of $315 billion, less than 2 percent of what it is today. The day after the funeral, senators rejected the grain export bill and endorsed the library money.

And by early afternoon Wednesday, the day before Thanksgiving, House members had returned to hear President Lyndon B. Johnson’s first speech to a joint session, in which he declared that enacting the long-stalled civil rights expansion would be the best possible tribute to his slain predecessor.

In just 120 hours, one era had ended in Congress and a new generation had begun.